My Tool set that I carry with me all the time is as follows:
Eff V Unbk III Fortune III Pickaxe
Eff VII Unbk III Silk I Pickaxe (Eff V when I didn't have an EFF VII)
Eff V Unbk III Silk I Spade
Eff V Unbk III Silk I Axe (Sometimes I have a Fort III)
Unbk III Lure III Luck of the Sea III Fishing Rod
Silk I Shears
Sharp 5 Looting III Sword (For mobs)
Sharp 5 Knockback II Fire Aspect II Sword (Only carry this for PVP stuff)

My Armor
Prot IV Resp III Aqua I Thorns III Unbk III Helmet
Prot IV Thorns III Unbk III Chest
Prot IV Thorns III Unbk III Legs
Prot IV Thorns III Unbk III Feather Falling IV Boots

 

When I leave the cave I make sure I'm armed thusly;

Armor:
Diamond Helm: Unbr III, Prot IV, Aff I, Asp III, thorns III
Diamond Chest: Unbr III, Prot IV, thorns III
Diamond Legs: Unbr III, Prot IV, thorns III
Diamond Boots: Unbr III, Prot IV, FFIV, thorns III

Tools and weaponry:
Pick Eff VII, StI, Unbr III
Pick Eff V, Fort III, Unbr III
Axe ST1, Eff V, Unbr III
Shears ST I, Eff V, Unbr III
Shovel ST I, Eff IV, Unbr III
Cooked Potatoes x 64
Torches x 64

 

I carry with me:

Sharpness V, Fire Aspect II, Knockback II, Looting III - Sword​

Efficiency VII, Unbreaking III, Silk Touch I - Pickaxe​

Efficiency V, Unbreaking III, Fortune III - Pickaxe​

Efficiency V, Unbreaking III, Fortune III - Shovel​

Efficiency V, Unbreaking III, Silk Touch I - Sheers​

Bucket​

 

For swords I'd say Looting III and for tools Silk Touch I = Fortune III

 

Strangely enough, after dealing in ebooks for quite some time, I find that the one I need the most and have one HECK of a time getting with any regularity is Unbreaking III.

It is always just taken for granted, yet it is the one ebook I refuse to sell. I'll even sell you a Thorns III or a Silk Touch or an Efficiency V but NOT Unbreaking III. Efficiency V is a pain to make, but (at least in the past) it was very doable at a reasonable price. Unbreaking III is the very devil to get and unreliable to create.

I suppose Eff V or Silktouch are the most popular, but if you have either or both of those on a tool, just try to find an Unbreaking III book to combo with it! I have spent more XP combining tool/tool (which costs SO much more than tool/book) to put Unbreaking III on equipment - too much, actually.

 

Fortune III/II is another great enchantment to get on diamond tools so you can get more diamonds/redstone for more profit. I find it popular among me and other people.

 

I would agree with the unbr3 comment, that book is the most valuable. It goes on anything and you want it on everything. Its not a default on the star tools and if your missing it on any item you want it.

 

I prefer no armor enchants because the colors affect my majestic green shirt blue pants combo. But I do love me a silk touch eff4 unb 3 pick axe and unb 3 is rare? I have like 3 or 4 of those books.

 

Its still the book that I have the least of (1) currently and I have a number of items that could do with it. Such as shears and swords but then my armoury is several updates old now.

 

Wow, that means all those great books I was going to sell will be useless, right? Bummer...

 

I voted for silk touch over Eff5 because silk touch accomplishes things that can't be done otherwise.